Parentage: The Rosa hybrida variety ‘KORtuberlou’ is the result of a controlled cross-pollination breeding program carried out by the inventor in Klein Offenseth-Sparrieshoop, Germany. The objective of the said breeding program was to create a new and distinct rose plant with unique qualities, such as:                1. Uniform growth habit and uniform flowering; and        2. Abundant, recurrent yellow flowers that are margined pink; and        3. Attractive and abundant foliage; and        4. Resistance to diseases encountered in landscapes and gardens.This combination of qualities is not present in prior rose cultivars known to the inventor. These objectives have been substantially achieved and in that distinguish ‘KORtuberlou’ from all other varieties known to the inventor.        
‘KORtuberlou’ is a seedling selection which resulted from the controlled pollination of Rosa hybrida ‘KORquelda’ (U.S. Plant Pat. No. 17,048), the seed parent, and with an unnamed Rosa hybrida seedling (unpatented) developed and owned by the same inventor, the pollen parent, during the summer of 2002. As part of a rose development program, Tim-Hermann Kordes germinated seeds from the aforementioned hybridization during the following winter and conducted evaluations and observations on the resulting seedlings in a controlled environment in Klein Offenseth-Sparrieshoop, Germany. The resulting seedlings exhibited distinctive physical and biological characteristics. The new rose plant was selected as a single plant in May of 2003 from the seedling beds due to its superior characteristics and asexually propagated for further evaluation. This new and distinctive rose variety was given the name ‘KORtuberlou’.
Asexual Reproduction: ‘KORtuberlou’ was first asexually propagated by bud grafting in July of 2003 at the inventor's nursery in Klein Offenseth-Sparrieshoop, Germany. Subsequently, ‘KORtuberlou’ has been successfully propagated by stem cuttings and bud grafting in Jackson County, Oreg. These initial and other subsequent propagations conducted in controlled environments demonstrate that ‘KORtuberlou’ reproduces true to type in successive generations of asexual reproduction.